@RoryAlsop, that looks for Arts & Crafts sort of how it looks for Travel--related to the site topics, and there are probably a few users who could answer it coincidentally, but at the edge. Most of the requirements this site deals with relate more to static appearance than dynamic performance. Picking the right foam for a performance requirement is more of an engineering or material science question.
As a frequent issue related to travel, Travel might have more potential answerers. But if it's off-topic for Travel, I wouldn't close it here myself, although I could envision some people seeing it as off-topic. Let's see if another mod weighs in.